vendor/gix-ref/src/store/file/log/line.rs

   1 use gix_hash::ObjectId;
   2
   3 use crate::{log::Line, store_impl::file::log::LineRef};
   4
   5 impl<'a> LineRef<'a> {
   6     /// Convert this instance into its mutable counterpart
   7     pub fn to_owned(&self) -> Line {
   8         self.clone().into()
   9     }
  10 }
  11
  12 mod write {
  13     use std::io;
  14
  15     use gix_object::bstr::{BStr, ByteSlice};
  16
  17     use crate::log::Line;
  18
  19     /// The Error produced by [`Line::write_to()`] (but wrapped in an io error).
  20     #[derive(Debug, thiserror::Error)]
  21     #[allow(missing_docs)]
  22     enum Error {
  23         #[error("Messages must not contain newlines\\n")]
  24         IllegalCharacter,
  25     }
  26
  27     impl From<Error> for io::Error {
  28         fn from(err: Error) -> Self {
  29             io::Error::new(io::ErrorKind::Other, err)
  30         }
  31     }
  32
  33     /// Output
  34     impl Line {
  35         /// Serialize this instance to `out` in the git serialization format for ref log lines.
  36         pub fn write_to(&self, mut out: impl io::Write) -> io::Result<()> {
  37             write!(out, "{} {} ", self.previous_oid, self.new_oid)?;
  38             self.signature.write_to(&mut out)?;
  39             writeln!(out, "\t{}", check_newlines(self.message.as_ref())?)
  40         }
  41     }
  42
  43     fn check_newlines(input: &BStr) -> Result<&BStr, Error> {
  44         if input.find_byte(b'\n').is_some() {
  45             return Err(Error::IllegalCharacter);
  46         }
  47         Ok(input)
  48     }
  49 }
  50
  51 impl<'a> LineRef<'a> {
  52     /// The previous object id of the ref. It will be a null hash if there was no previous id as
  53     /// this ref is being created.
  54     pub fn previous_oid(&self) -> ObjectId {
  55         ObjectId::from_hex(self.previous_oid).expect("parse validation")
  56     }
  57     /// The new object id of the ref, or a null hash if it is removed.
  58     pub fn new_oid(&self) -> ObjectId {
  59         ObjectId::from_hex(self.new_oid).expect("parse validation")
  60     }
  61 }
  62
  63 impl<'a> From<LineRef<'a>> for Line {
  64     fn from(v: LineRef<'a>) -> Self {
  65         Line {
  66             previous_oid: v.previous_oid(),
  67             new_oid: v.new_oid(),
  68             signature: v.signature.into(),
  69             message: v.message.into(),
  70         }
  71     }
  72 }
  73
  74 ///
  75 pub mod decode {
  76     use gix_object::bstr::{BStr, ByteSlice};
  77     use nom::{
  78         bytes::complete::{tag, take_while},
  79         combinator::opt,
  80         error::{context, ContextError, ParseError},
  81         sequence::{terminated, tuple},
  82         IResult,
  83     };
  84
  85     use crate::{file::log::LineRef, parse::hex_hash};
  86
  87     ///
  88     mod error {
  89         use gix_object::bstr::{BString, ByteSlice};
  90
  91         /// The error returned by [from_bytes(…)][super::Line::from_bytes()]
  92         #[derive(Debug)]
  93         pub struct Error {
  94             pub input: BString,
  95         }
  96
  97         impl std::fmt::Display for Error {
  98             fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
  99                 write!(
 100                     f,
 101                     "{:?} did not match '<old-hexsha> <new-hexsha> <name> <<email>> <timestamp> <tz>\\t<message>'",
 102                     self.input
 103                 )
 104             }
 105         }
 106
 107         impl std::error::Error for Error {}
 108
 109         impl Error {
 110             pub(crate) fn new(input: &[u8]) -> Self {
 111                 Error {
 112                     input: input.as_bstr().to_owned(),
 113                 }
 114             }
 115         }
 116     }
 117     pub use error::Error;
 118
 119     impl<'a> LineRef<'a> {
 120         /// Decode a line from the given bytes which are expected to start at a hex sha.
 121         pub fn from_bytes(input: &'a [u8]) -> Result<LineRef<'a>, Error> {
 122             one::<()>(input).map(|(_, l)| l).map_err(|_| Error::new(input))
 123         }
 124     }
 125
 126     fn message<'a, E: ParseError<&'a [u8]>>(i: &'a [u8]) -> IResult<&'a [u8], &'a BStr, E> {
 127         if i.is_empty() {
 128             Ok((&[], i.as_bstr()))
 129         } else {
 130             terminated(take_while(|c| c != b'\n'), opt(tag(b"\n")))(i).map(|(i, o)| (i, o.as_bstr()))
 131         }
 132     }
 133
 134     fn one<'a, E: ParseError<&'a [u8]> + ContextError<&'a [u8]>>(bytes: &'a [u8]) -> IResult<&[u8], LineRef<'a>, E> {
 135         let (i, (old, new, signature, message_sep, message)) = context(
 136             "<old-hexsha> <new-hexsha> <name> <<email>> <timestamp> <tz>\\t<message>",
 137             tuple((
 138                 context("<old-hexsha>", terminated(hex_hash, tag(b" "))),
 139                 context("<new-hexsha>", terminated(hex_hash, tag(b" "))),
 140                 context("<name> <<email>> <timestamp>", gix_actor::signature::decode),
 141                 opt(tag(b"\t")),
 142                 context("<optional message>", message),
 143             )),
 144         )(bytes)?;
 145
 146         if message_sep.is_none() {
 147             if let Some(first) = message.first() {
 148                 if !first.is_ascii_whitespace() {
 149                     return Err(nom::Err::Error(E::add_context(
 150                         i,
 151                         "log message must be separated from signature with whitespace",
 152                         E::from_error_kind(i, nom::error::ErrorKind::MapRes),
 153                     )));
 154                 }
 155             }
 156         }
 157
 158         Ok((
 159             i,
 160             LineRef {
 161                 previous_oid: old,
 162                 new_oid: new,
 163                 signature,
 164                 message,
 165             },
 166         ))
 167     }
 168
 169     #[cfg(test)]
 170     mod test {
 171         use gix_actor::{Sign, Time};
 172         use gix_object::bstr::ByteSlice;
 173
 174         use super::*;
 175
 176         /// Convert a hexadecimal hash into its corresponding `ObjectId` or _panic_.
 177         fn hex_to_oid(hex: &str) -> gix_hash::ObjectId {
 178             gix_hash::ObjectId::from_hex(hex.as_bytes()).expect("40 bytes hex")
 179         }
 180
 181         fn with_newline(mut v: Vec<u8>) -> Vec<u8> {
 182             v.push(b'\n');
 183             v
 184         }
 185
 186         mod invalid {
 187             use gix_testtools::to_bstr_err;
 188             use nom::error::VerboseError;
 189
 190             use super::one;
 191
 192             #[test]
 193             fn completely_bogus_shows_error_with_context() {
 194                 let err = one::<VerboseError<&[u8]>>(b"definitely not a log entry")
 195                     .map_err(to_bstr_err)
 196                     .expect_err("this should fail");
 197                 assert!(err.to_string().contains("<old-hexsha> <new-hexsha>"));
 198             }
 199
 200             #[test]
 201             fn missing_whitespace_between_signature_and_message() {
 202                 let line = "0000000000000000000000000000000000000000 0000000000000000000000000000000000000000 one <foo@example.com> 1234567890 -0000message";
 203                 let err = one::<VerboseError<&[u8]>>(line.as_bytes())
 204                     .map_err(to_bstr_err)
 205                     .expect_err("this should fail");
 206                 assert!(err
 207                     .to_string()
 208                     .contains("log message must be separated from signature with whitespace"));
 209             }
 210         }
 211
 212         const NULL_SHA1: &[u8] = b"0000000000000000000000000000000000000000";
 213
 214         #[test]
 215         fn entry_with_empty_message() {
 216             let line_without_nl: Vec<_> = b"0000000000000000000000000000000000000000 0000000000000000000000000000000000000000 name <foo@example.com> 1234567890 -0000".to_vec();
 217             let line_with_nl = with_newline(line_without_nl.clone());
 218             for input in &[line_without_nl, line_with_nl] {
 219                 assert_eq!(
 220                     one::<nom::error::Error<_>>(input).expect("successful parsing").1,
 221                     LineRef {
 222                         previous_oid: NULL_SHA1.as_bstr(),
 223                         new_oid: NULL_SHA1.as_bstr(),
 224                         signature: gix_actor::SignatureRef {
 225                             name: b"name".as_bstr(),
 226                             email: b"foo@example.com".as_bstr(),
 227                             time: Time {
 228                                 seconds_since_unix_epoch: 1234567890,
 229                                 offset_in_seconds: 0,
 230                                 sign: Sign::Minus
 231                             }
 232                         },
 233                         message: b"".as_bstr(),
 234                     }
 235                 );
 236             }
 237         }
 238
 239         #[test]
 240         fn entry_with_message_without_newline_and_with_newline() {
 241             let line_without_nl: Vec<_> = b"a5828ae6b52137b913b978e16cd2334482eb4c1f 89b43f80a514aee58b662ad606e6352e03eaeee4 Sebastian Thiel <foo@example.com> 1618030561 +0800\tpull --ff-only: Fast-forward".to_vec();
 242             let line_with_nl = with_newline(line_without_nl.clone());
 243
 244             for input in &[line_without_nl, line_with_nl] {
 245                 let (remaining, res) = one::<nom::error::Error<_>>(input).expect("successful parsing");
 246                 assert!(remaining.is_empty(), "all consuming even without trailing newline");
 247                 let actual = LineRef {
 248                     previous_oid: b"a5828ae6b52137b913b978e16cd2334482eb4c1f".as_bstr(),
 249                     new_oid: b"89b43f80a514aee58b662ad606e6352e03eaeee4".as_bstr(),
 250                     signature: gix_actor::SignatureRef {
 251                         name: b"Sebastian Thiel".as_bstr(),
 252                         email: b"foo@example.com".as_bstr(),
 253                         time: Time {
 254                             seconds_since_unix_epoch: 1618030561,
 255                             offset_in_seconds: 28800,
 256                             sign: Sign::Plus,
 257                         },
 258                     },
 259                     message: b"pull --ff-only: Fast-forward".as_bstr(),
 260                 };
 261                 assert_eq!(res, actual);
 262                 assert_eq!(
 263                     actual.previous_oid(),
 264                     hex_to_oid("a5828ae6b52137b913b978e16cd2334482eb4c1f")
 265                 );
 266                 assert_eq!(actual.new_oid(), hex_to_oid("89b43f80a514aee58b662ad606e6352e03eaeee4"));
 267             }
 268         }
 269
 270         #[test]
 271         fn two_lines_in_a_row_with_and_without_newline() {
 272             let lines = b"0000000000000000000000000000000000000000 0000000000000000000000000000000000000000 one <foo@example.com> 1234567890 -0000\t\n0000000000000000000000000000000000000000 0000000000000000000000000000000000000000 two <foo@example.com> 1234567890 -0000\thello";
 273             let (remainder, parsed) = one::<nom::error::Error<_>>(lines).expect("parse single line");
 274             assert_eq!(parsed.message, b"".as_bstr(), "first message is empty");
 275
 276             let (remainder, parsed) = one::<nom::error::Error<_>>(remainder).expect("parse single line");
 277             assert_eq!(
 278                 parsed.message,
 279                 b"hello".as_bstr(),
 280                 "second message is not and contains no newline"
 281             );
 282             assert!(remainder.is_empty());
 283         }
 284     }
 285 }